Conventionally, as one of refrigerating apparatus that perform a multistage compression refrigeration cycle using a refrigerant that works in a supercritical region, there is an air conditioning apparatus such as described in Japanese Patent Publication No. 2007-232263 that performs a two-stage compression refrigeration cycle using carbon dioxide as the refrigerant. This air conditioning apparatus mainly has a compressor having two compression elements connected in series, an outdoor heat exchanger, an expansion valve, and an indoor heat exchanger.